why temperature scale?

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Anonymous
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In the RTD example project provided in PSoC Creator 2.1,what is the significance of using the temperature scale in 'main.c'?

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Bob_Marlowe
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A PT100 has a temp range of -200°C to +850°C which is superiour to any semi-conductor sensor. Together with the calibration to get rid of the non-linearities a max precision of 0.01°C within an interval can be archieved.

   

Have a look into the component's datasheet, under the header "General" you'll find a short description what the component is and what it is good for.

   

 

   

Happy coding

   

Bob

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ETRO_SSN583
Level 9
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At first I thought it was to get to volts as the RTD is 100 ohms. Eg. its actually

   

a scale factor for the RTD not being 1 ohm. But I am not sure. Contact the

   

author of the ap note, and re-post here the answer.

   

 

   

Praveen Sekar [pfz@cysemi.com]

   

 

   

Regards, Dana.

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Anonymous
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Poorva,

   

There are 2 projects with AN70698. 1. RTD temperature measurement, 2. Broken RTD reconfiguration

   

Which line of code in main.c are you referring to? 

   

Regards,

   

Praveen

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ETRO_SSN583
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I can't speak for original poster but in PSOC 3 RTD Example project in

   

Creator, line 28, there is a define -

   

 

   

   

   

#define TEMP_SCALE (100u)

   

 

and used line 140 -

rtdTempDisp = (float) rtdTemp / TEMP_SCALE ;

 

Regards, Dana.

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Anonymous
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 Hi Dana,

   

Where did you download the RTD example project from?

   

Regards,

   

Praveen

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ETRO_SSN583
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In Creator, an example project, 5.1

   

 

   

Regards, Dana.

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Anonymous
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Praveen Sir,

   

The RTD temperature measurement project.Lines 28,29 and 140 in main.c

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Anonymous
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 Poorva/Dana,

   

The RTD_GetTemperature() API takes resistance in milliohms as argument and returns temperature in 1/100th of a degree celcius.

   

The temperature scale and resistance scale aid in converting temperature in 1/100th of a degree celcius to degree celcius and resistance in milliohms to resistance in ohms respectively

   

Regards,

   

Praveen

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